This invention relates to endoscopes for inspecting inner cavities of a patient""s body, particularly those associated with the gastro-intestinal tract. More particularly, the invention relates to an endoscope with a disposable core for minimizing the cost, and facilitating the ease, of examining the inner cavities of the patient""s body. The endoscope of this invention is particularly advantageous in minimizing any likelihood of cross contaminating successive patients.
The examination of the inner cavities of a patient""s body for evidences of cancer, and for polyps which sometimes lead to cancer, is becoming increasingly common. Endoscopes are employed to make such examinations. One type of endoscope employs a video sensor in the distal tip section, which sensor electrically senses the image as by a charge coupled device and sends information relating to the sensed image from the charge coupled device through a set of wires to processing and display means outside the endoscope.
Another type of endoscope generally includes at least one illuminating lens on a display face of the endoscope to illuminate the portion of the inner body cavity being inspected and also includes an imaging lens for receiving the image from the illuminated portion of the inner body cavity. Optical fibers are provided in this type of endoscope for introducing light to the illuminating lens and for receiving light from the imaging lens. The endoscopes also have passageways for obtaining specimens from the inner cavities of the patient""s body such as the patient""s colon. These passageways provide for obtaining specimens from the patient""s inner body cavity as by suction or vacuum or as by an instrument such as forceps. The passageways may be used for other purposes such as polyp snaring, cauterizing or ablation as by lasers.
There are certain inherent limitations or disadvantages in the endoscopes now in use. One inherent disadvantage or limitation is that the endoscopes tend to provide cross contamination from a first patient to a second patient when an examination is made initially of the inner body cavity of the first patient and then of the second patient. Elaborate procedures are performed on an endoscope to clean and disinfect the endoscope after each examination of a patient""s inner body cavity but such elaborate procedures are not always effective, especially with respect to cleaning the inner passageways.
To overcome the problems discussed in the previous paragraph, endoscopes have been made modular. For example, the shell holding the lenses and passageways described in the previous paragraph has been made disposable. After the inner cavity such as the colon of an individual patient has been examined, the shell has been removed and discarded. The endoscope has then been cleaned and a new shell has then been disposed on the endoscope for the examination of another patient""s inner body cavity.
The procedure described in the previous paragraph has been cumbersome and expensive, particularly since the illuminating and imaging lenses have been included in the disposable shell. With the efforts now being made to limit the costs of medical procedures, endoscopes with disposable shells are becoming progressively undesirable. Furthermore, it has been found necessary to disinfect the endoscope even after the shell has been removed from the endoscope due to contamination of other parts of the endoscope not protected by the shell.
This invention provides an endoscope which overcomes the above disadvantages. The invention includes a disposable core which is removably disposed in a lumen in a shell. The disposable core is removable from the shell lumen after an inspection of an individual""s inner body cavity, and the shell lumen is cleaned. Another core is then disposed in the shell lumen for an inspection of the inner body cavity of a second patient. The disposable core of this invention may be provided with features for cleaning the shell lumen as the core is drawn into the shell lumen.
In one embodiment of the invention, an endoscope for insertion into a patient""s inner body cavity has a resilient shell with lumens (1) for illuminating an illuminating lens and (2) for passing light from an imaging (or objective) lens, each lens being disposed on the distal face of the shell. The shell also has a lumen, preferably off-round, for receiving a resilient disposable core. The disposable core has passageways for introducing a pressurized fluid (e.g. air or water) to selective ones of the lenses to clean the lenses.
The core may also have another passageway for removing material from the patient""s inner body cavity for analysis. This passageway may communicate with two (2) conduits for removing specimens from the colon (1) as by a vacuum and (2) as by an instrument. The second conduit may be closed except when the instrument is to be inserted into a patient""s inner body cavity.
The core may be drawn through the shell lumen to position the core in the lumen. A cleaning member may be attached to the core to clean the shell lumen as the core is drawn through the lumen. Alternatively, a leader applied to the core may be drawn with the core through the shell lumen and then removed from the core.
Sealing members attached to the core may also be drawn through the lumen with the core to seal the core to the shell at each end so as to prevent contamination from leaking into the lumen. Alternatively, members may be sealed to the core or shell after the drawing operation. A cover on a core end may alternatively be removed after the core has been drawn through the shell lumen.